Ultrasound imaging is an increasingly used tool for medical screening and early detection of breast cancer, especially for patients with dense breast tissue. Ultrasound systems may include either a handheld probe or an automated scanning system connected to an imaging system. These systems generate ultrasonic waves, which permeate the tissue of a patient, and partially reflect back to the source. A transducer then converts the reflected echo waves into electrical signals. The imaging system uses the electrical signals to construct images (e.g., two-dimensional or three-dimensional images.)
Handheld probes allow freeform movement, which makes it easier for an operator to scan, for example, various contours of a patient with the probe. However, because handheld probes have limited image reproduction capabilities, handheld probes have been generally used for diagnosis, not for screening.
Handheld probes also may rely on the skill of the operator, thereby limiting screening capabilities. For example, an unskilled practitioner may apply too much pressure on the tissue with the probe, causing the tissue to deform resulting in a distorted image. Conversely, not applying enough pressure may result in sub-optimal image quality. As another example, holding the probe at an oblique angle in relation to the tissue may also degrade image quality.
Handheld probes do not conventionally collect operational information that would allow an imaging system to assist the operator. Additionally, due to the free form nature of handheld systems, variations in image quality and inconsistent screenings may result from handheld imaging systems.
Automated whole-breast ultrasound systems are known that provide screening capabilities. However, automated systems may be bulky and/or costly. For example, some automated systems have a specially designed curved ultrasound probe with special immobilizer material between the tissue and the scan probe, which may be bulky. Other automated systems provide limited scan area coverage. Other systems provide no real-time feedback. Additionally, automated systems conventionally are not portable or easily portable. As such, automated systems are not a viable option for medical practitioners in developing countries.